It's not as complicated as you think. Let's go over the fundamentals for victory shall we:
First and most important: Win the line of scrimmage on both sides of the ball. Teams that do that win in the playoffs. teams that don't go home.
Tebow time needs to start in the first quarter and continue for 60 minutes. Last 3 games I haven't seen that 60 minute attitude.
Win Special Teams. No big returns against us and spring our return guys lose. Pin them down in the punting game. Steelers are not a long drive offense. Win the field position battle and our odds increase dramatically.
Play nasty. Steelers like to think they are big bad bullies and can intimidate you. If you bully them back they don't play as well. Just ask the Niners and Ravens.
No damn turnovers. Those have killed us recently.
Create some turnovers. When we were winning, our defense was creating fumbles and interceptions.
Beat the snot out of them. They have less talent than you think, and they're old. The Steelers are beat up coming into this game. At altitude we need to wear them out, especially their defensive linemen and backers. They have an old front seven. And their O-line is no great shakes either. Now is your time. Come out hitting them in the mouth and don't let up. Broncos, you are the better conditioned team, so use it to your advantage.
Don't get too fancy on outside runs -- play smash mouth between the tackles. Steelers play fast but can be beat up the middle (see, for example Hillis' runs against them last game) if the O-Line gets off on their blocks, especially when they get to the second level.
Pass more on first down with play fakes and give Tebow more check downs. Too often it seems he's looking for that one big passing play. I don't know if this is a play calling issue or not, but if the long pass isn't there he needs to recognize it and find his hot receivers. A five yard pass on first down is a win.
Come out in a hurry up, with two tight ends, 1 back and two WR's. Split Rosario and Fells (or whoever) out as slot receivers but still close enough to become crack back blockers on running plays. Don;t shpow them the same old formations they've already seen on tape.
If you show option looks, pass out of them, instead of running all the time, especially if the Steeler linebackers and Polamalu are coming down to protect the edge and cover inside gaps to stop the run. Quick slants to wide outs or TE's should be open or seam passes to TE's if LB's are playing contain and not blitzing.
As for Messrs. Decker, Willis, Royal and Thomas, I have 2 words: no drops. You never know how many chances you will have to play in the tournament so bring your A game.
Pressure the hell out of Roethlisberger. Sacks would be nice but hurries are just as good. With his bad ankle his passing accuracy goes way down when he's pressured, especially when the pressure comes from up the middle (watch tape of his games at SF and Cleveland).
Tackle. Tackle. Tackle. Yards after Catch (YAC) killed us in Buffalo and against NE. So did yards after first contact by running backs.
Our playmakers have to come up big. On defense let's see some sacks from Von Doom, some fumbles and some interceptions. To paraphrase LT (the original) you all need to play like mad dogs out there.
And Mr. Bailey, sir, I remember what you did to Tom "the Nephew of God" Brady in 2006. That was a Champ type play that day. It won the game. Time to make that kind of dagger to the heart play again.
Foxy - go for it on 4th down sometimes. What have you got to lose? And If Prater is in range for a 57 yd FG take it. You trusted him all season. Trust him now.
Coaching adjustments: Don't wait for halftime. And don't waste the second quarter once they know how the first quarter went. You know the Steelers' coaches won't wait to adjust to what you're doing. Pull some surprises out of your hat early and often. Do the unexpected sooner.
You fans at the stadium, stay loud the whole game. Don't pay attention to the score. Just keep screaming. You should all be hoarse the next day (pun intended). Players appreciate that fans haven't given up on them even when they fall behind.
Most important of all, don't think you can win, don't believe you can win. Know you will win.